book-2

22 STRUCTURE AS ARCHITECTUREIt is worth noting that although Erickson postpones structural decisionsin the early design stages, his architecture is notable for its rational andclearly expressed structure. His buildings lack any evidence of conceptualstructural design decisions being left too late in the design process, resultingin structure poorly integrated with building function and aesthetics.One just needs to recall his Vancouver Law Courts building and theMuseum of Anthropology, University of British Columbia, Vancouver, toappreciate the clarity with which structure ‘speaks’ in his architecture.Such an attitude towards structure as ‘form-follower’ rather than ‘formgiver’contrasts starkly with opposing views that have been articulatedin various periods of architectural history. For example, Viollet-le-Ducexpressed the views of eighteenth-century Structural Rationalists:‘Imposeon me a structural system, and I will naturally find you the forms whichshould result from it. But if you change the structure, I shall be obliged tochange the forms.’ 4 He spoke with Gothic architecture in mind, wheremasonry load-bearing walls and buttresses comprise the building envelope.By virtue of its large plan area and its exterior and interior spatialimpact, structure so dominates Gothic construction that a close relationshipexists between structural and architectural form. However, sincethe eighteenth century and the advent of high-strength tension-capablematerials like iron and then steel, the previously limited structural vocabularyof walls, vaults and buttresses has been extended greatly and oftenbeen relieved of the task of enveloping buildings. Newer systems likemoment frames and cantilever columns are common, and these are usedin conjunction with modern non-structural enveloping systems such asprecast concrete and light-weight panels. Building enclosure is now frequentlyseparated from the structure to the extent that the structuralform may be quite unexpected given the architectural form.Viollet-le-Duc’s beliefs in structure as ‘form-giver’ were reaffirmed justas forcefully in the 1950s by Pier Luigi Nervi:Moreover, I am deeply convinced – and this conviction is strengthened bya critical appraisal of the most significant architectural works of the pastas well as of the present – that the outward appearance of a good buildingcannot, and must not, be anything but the visible expression of anefficient structural or constructional reality. In other words, form must bethe necessary result, and not the initial basis of structure. 5Nervi’s view, persuasive only in the context of high-rise and long-spanconstruction, is supported by Glasser: ‘as in the case of arenas, auditoriums,and stadiums – it is equally clear that a conceptual design without arigorous and well-integrated structural framework would be specious.’ 6